Asthma is a chronic lung disease that narrows airways, making breathing difficult. It is the most common chronic breathing condition of childhood. Asthma generally persists into adulthood and most patients never grow out of the disease. Approximately 20 percent of adults with asthma, develop the condition for the first time as an adult.

Asthma affects more than 22 million people in the United States, almost 6 million of which are children, according to the National Heart Lung and Blood Institute, part of the National Institutes of Health.


The symptoms of asthma include:
  • Coughing
  • Wheezing
  • Chest tightness
  • Shortness of breath


Asthma symptoms can be caused by:
  • Allergens, such as dust, animal fur, cockroaches, mold, pollen, grasses and flowers
  • Irritants, such as cigarette smoke, air pollution or chemicals
  • Certain medications, such as aspirin
  • Sulfites in foods or drinks
  • Viral upper respiratory infections, such as colds
  • Exercise

Risk Factors

The risk factors for asthma include:
  • Frequent respiratory illnesses as a child
  • Exposure to secondhand smoke or air pollution
  • Low birth weight or being overweight
  • Poverty and low socioeconomic status
  • Substandard housing
  • Indoor allergens
  • Inadequate access to health care
  • Family history, although many people without a family history develop asthma


Asthma is diagnosed with the following tools:
  • Pulmonary function testing to determine airflow obstruction and other lung conditions
  • Peak Expiratory Flow measurements at home
  • Methacholine challenge
  • Exercise challenge
  • Skin prick testing to determine allergies that could trigger asthma
  • Laboratory tests


Uncontrolled asthma can reduce health-related quality of life, causing complications, such as:
  • School absenteeism
  • Home confinement
  • Coughing
  • Shortness of breath
  • Inability to participate in sports and activities
  • Hospitalization
  • Life-threatening breathing difficulty


People with asthma should identify and avoid their asthma triggers, learn to recognize warning signs of worsening asthma and take medication as prescribed, even if their asthma seems to be improving. Those with the condition should also see their provider for regular check-ups.

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